Files
LEANN/packages/leann-core/src/leann/embedding_compute.py
2025-07-22 19:38:22 -07:00

376 lines
13 KiB
Python

"""
Unified embedding computation module
Consolidates all embedding computation logic using SentenceTransformer
Preserves all optimization parameters to ensure performance
"""
import numpy as np
import torch
from typing import List, Dict, Any
import logging
import os
# Set up logger with proper level
logger = logging.getLogger(__name__)
LOG_LEVEL = os.getenv("LEANN_LOG_LEVEL", "WARNING").upper()
log_level = getattr(logging, LOG_LEVEL, logging.WARNING)
logger.setLevel(log_level)
# Global model cache to avoid repeated loading
_model_cache: Dict[str, Any] = {}
def compute_embeddings(
texts: List[str],
model_name: str,
mode: str = "sentence-transformers",
is_build: bool = False,
batch_size: int = 32,
adaptive_optimization: bool = True,
) -> np.ndarray:
"""
Unified embedding computation entry point
Args:
texts: List of texts to compute embeddings for
model_name: Model name
mode: Computation mode ('sentence-transformers', 'openai', 'mlx')
is_build: Whether this is a build operation (shows progress bar)
batch_size: Batch size for processing
adaptive_optimization: Whether to use adaptive optimization based on batch size
Returns:
Normalized embeddings array, shape: (len(texts), embedding_dim)
"""
if mode == "sentence-transformers":
return compute_embeddings_sentence_transformers(
texts,
model_name,
is_build=is_build,
batch_size=batch_size,
adaptive_optimization=adaptive_optimization,
)
elif mode == "openai":
return compute_embeddings_openai(texts, model_name)
elif mode == "mlx":
return compute_embeddings_mlx(texts, model_name)
else:
raise ValueError(f"Unsupported embedding mode: {mode}")
def compute_embeddings_sentence_transformers(
texts: List[str],
model_name: str,
use_fp16: bool = True,
device: str = "auto",
batch_size: int = 32,
is_build: bool = False,
adaptive_optimization: bool = True,
) -> np.ndarray:
"""
Compute embeddings using SentenceTransformer with model caching and adaptive optimization
Args:
texts: List of texts to compute embeddings for
model_name: Model name
use_fp16: Whether to use FP16 precision
device: Device to use ('auto', 'cuda', 'mps', 'cpu')
batch_size: Batch size for processing
is_build: Whether this is a build operation (shows progress bar)
adaptive_optimization: Whether to use adaptive optimization based on batch size
"""
# Handle empty input
if not texts:
raise ValueError("Cannot compute embeddings for empty text list")
logger.info(
f"Computing embeddings for {len(texts)} texts using SentenceTransformer, model: '{model_name}'"
)
# Auto-detect device
if device == "auto":
if torch.cuda.is_available():
device = "cuda"
elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
device = "mps"
else:
device = "cpu"
# Apply optimizations based on benchmark results
if adaptive_optimization:
# Use optimal batch_size constants for different devices based on benchmark results
if device == "mps":
batch_size = 128 # MPS optimal batch size from benchmark
if model_name == "Qwen/Qwen3-Embedding-0.6B":
batch_size = 64
elif device == "cuda":
batch_size = 256 # CUDA optimal batch size
# Keep original batch_size for CPU
# Create cache key
cache_key = f"sentence_transformers_{model_name}_{device}_{use_fp16}_optimized"
# Check if model is already cached
if cache_key in _model_cache:
logger.info(f"Using cached optimized model: {model_name}")
model = _model_cache[cache_key]
else:
logger.info(
f"Loading and caching optimized SentenceTransformer model: {model_name}"
)
from sentence_transformers import SentenceTransformer
logger.info(f"Using device: {device}")
# Apply hardware optimizations
if device == "cuda":
# TODO: Haven't tested this yet
torch.backends.cuda.matmul.allow_tf32 = True
torch.backends.cudnn.allow_tf32 = True
torch.backends.cudnn.benchmark = True
torch.backends.cudnn.deterministic = False
torch.cuda.set_per_process_memory_fraction(0.9)
elif device == "mps":
try:
if hasattr(torch.mps, "set_per_process_memory_fraction"):
torch.mps.set_per_process_memory_fraction(0.9)
except AttributeError:
logger.warning(
"Some MPS optimizations not available in this PyTorch version"
)
elif device == "cpu":
# TODO: Haven't tested this yet
torch.set_num_threads(min(8, os.cpu_count() or 4))
try:
torch.backends.mkldnn.enabled = True
except AttributeError:
pass
# Prepare optimized model and tokenizer parameters
model_kwargs = {
"torch_dtype": torch.float16 if use_fp16 else torch.float32,
"low_cpu_mem_usage": True,
"_fast_init": True,
"attn_implementation": "eager", # Use eager attention for speed
}
tokenizer_kwargs = {
"use_fast": True,
"padding": True,
"truncation": True,
}
try:
# Try local loading first
model_kwargs["local_files_only"] = True
tokenizer_kwargs["local_files_only"] = True
model = SentenceTransformer(
model_name,
device=device,
model_kwargs=model_kwargs,
tokenizer_kwargs=tokenizer_kwargs,
local_files_only=True,
)
logger.info("Model loaded successfully! (local + optimized)")
except Exception as e:
logger.warning(f"Local loading failed ({e}), trying network download...")
# Fallback to network loading
model_kwargs["local_files_only"] = False
tokenizer_kwargs["local_files_only"] = False
model = SentenceTransformer(
model_name,
device=device,
model_kwargs=model_kwargs,
tokenizer_kwargs=tokenizer_kwargs,
local_files_only=False,
)
logger.info("Model loaded successfully! (network + optimized)")
# Apply additional optimizations based on mode
if use_fp16 and device in ["cuda", "mps"]:
try:
model = model.half()
logger.info(f"Applied FP16 precision: {model_name}")
except Exception as e:
logger.warning(f"FP16 optimization failed: {e}")
# Apply torch.compile optimization
if device in ["cuda", "mps"]:
try:
model = torch.compile(model, mode="reduce-overhead", dynamic=True)
logger.info(f"Applied torch.compile optimization: {model_name}")
except Exception as e:
logger.warning(f"torch.compile optimization failed: {e}")
# Set model to eval mode and disable gradients for inference
model.eval()
for param in model.parameters():
param.requires_grad_(False)
# Cache the model
_model_cache[cache_key] = model
logger.info(f"Model cached: {cache_key}")
# Compute embeddings with optimized inference mode
logger.info(f"Starting embedding computation... (batch_size: {batch_size})")
# Use torch.inference_mode for optimal performance
with torch.inference_mode():
embeddings = model.encode(
texts,
batch_size=batch_size,
show_progress_bar=is_build, # Don't show progress bar in server environment
convert_to_numpy=True,
normalize_embeddings=False,
device=device,
)
logger.info(
f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}"
)
# Validate results
if np.isnan(embeddings).any() or np.isinf(embeddings).any():
raise RuntimeError(
f"Detected NaN or Inf values in embeddings, model: {model_name}"
)
return embeddings
def compute_embeddings_openai(texts: List[str], model_name: str) -> np.ndarray:
# TODO: @yichuan-w add progress bar only in build mode
"""Compute embeddings using OpenAI API"""
try:
import openai
import os
except ImportError as e:
raise ImportError(f"OpenAI package not installed: {e}")
api_key = os.getenv("OPENAI_API_KEY")
if not api_key:
raise RuntimeError("OPENAI_API_KEY environment variable not set")
# Cache OpenAI client
cache_key = "openai_client"
if cache_key in _model_cache:
client = _model_cache[cache_key]
else:
client = openai.OpenAI(api_key=api_key)
_model_cache[cache_key] = client
logger.info("OpenAI client cached")
logger.info(
f"Computing embeddings for {len(texts)} texts using OpenAI API, model: '{model_name}'"
)
# OpenAI has limits on batch size and input length
max_batch_size = 100 # Conservative batch size
all_embeddings = []
try:
from tqdm import tqdm
total_batches = (len(texts) + max_batch_size - 1) // max_batch_size
batch_range = range(0, len(texts), max_batch_size)
batch_iterator = tqdm(
batch_range, desc="Computing embeddings", unit="batch", total=total_batches
)
except ImportError:
# Fallback when tqdm is not available
batch_iterator = range(0, len(texts), max_batch_size)
for i in batch_iterator:
batch_texts = texts[i : i + max_batch_size]
try:
response = client.embeddings.create(model=model_name, input=batch_texts)
batch_embeddings = [embedding.embedding for embedding in response.data]
all_embeddings.extend(batch_embeddings)
except Exception as e:
logger.error(f"Batch {i} failed: {e}")
raise
embeddings = np.array(all_embeddings, dtype=np.float32)
logger.info(
f"Generated {len(embeddings)} embeddings, dimension: {embeddings.shape[1]}"
)
return embeddings
def compute_embeddings_mlx(
chunks: List[str], model_name: str, batch_size: int = 16
) -> np.ndarray:
# TODO: @yichuan-w add progress bar only in build mode
"""Computes embeddings using an MLX model."""
try:
import mlx.core as mx
from mlx_lm.utils import load
except ImportError as e:
raise RuntimeError(
"MLX or related libraries not available. Install with: uv pip install mlx mlx-lm"
) from e
logger.info(
f"Computing embeddings for {len(chunks)} chunks using MLX model '{model_name}' with batch_size={batch_size}..."
)
# Cache MLX model and tokenizer
cache_key = f"mlx_{model_name}"
if cache_key in _model_cache:
logger.info(f"Using cached MLX model: {model_name}")
model, tokenizer = _model_cache[cache_key]
else:
logger.info(f"Loading and caching MLX model: {model_name}")
model, tokenizer = load(model_name)
_model_cache[cache_key] = (model, tokenizer)
logger.info(f"MLX model cached: {cache_key}")
# Process chunks in batches with progress bar
all_embeddings = []
try:
from tqdm import tqdm
batch_iterator = tqdm(
range(0, len(chunks), batch_size), desc="Computing embeddings", unit="batch"
)
except ImportError:
batch_iterator = range(0, len(chunks), batch_size)
for i in batch_iterator:
batch_chunks = chunks[i : i + batch_size]
# Tokenize all chunks in the batch
batch_token_ids = []
for chunk in batch_chunks:
token_ids = tokenizer.encode(chunk) # type: ignore
batch_token_ids.append(token_ids)
# Pad sequences to the same length for batch processing
max_length = max(len(ids) for ids in batch_token_ids)
padded_token_ids = []
for token_ids in batch_token_ids:
# Pad with tokenizer.pad_token_id or 0
padded = token_ids + [0] * (max_length - len(token_ids))
padded_token_ids.append(padded)
# Convert to MLX array with batch dimension
input_ids = mx.array(padded_token_ids)
# Get embeddings for the batch
embeddings = model(input_ids)
# Mean pooling for each sequence in the batch
pooled = embeddings.mean(axis=1) # Shape: (batch_size, hidden_size)
# Convert batch embeddings to numpy
for j in range(len(batch_chunks)):
pooled_list = pooled[j].tolist() # Convert to list
pooled_numpy = np.array(pooled_list, dtype=np.float32)
all_embeddings.append(pooled_numpy)
# Stack numpy arrays
return np.stack(all_embeddings)